<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>

<script>
  var json1 = {
    "name":"jack",
    "age":"18",
    "hobby":"sleeping"
    };
  console.log(json1.age);

  var json2 = {
      "array":[{
          "name":"jack",
          "age":"18",
          "hobby":"sleeping"
      }],
      "age":"18"
  }

  console.log(json2.array[0].age);
</script>
<body>
</body>
</html>